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-rw-r--r--include/llvm/CodeGen/LiveInterval.h193
1 files changed, 96 insertions, 97 deletions
diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h
index 29e689a52145..88131fbc40ff 100644
--- a/include/llvm/CodeGen/LiveInterval.h
+++ b/include/llvm/CodeGen/LiveInterval.h
@@ -21,7 +21,7 @@
#ifndef LLVM_CODEGEN_LIVEINTERVAL_H
#define LLVM_CODEGEN_LIVEINTERVAL_H
-#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/IntEqClasses.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/AlignOf.h"
#include "llvm/CodeGen/SlotIndexes.h"
@@ -39,32 +39,17 @@ namespace llvm {
/// This class holds information about a machine level values, including
/// definition and use points.
///
- /// Care must be taken in interpreting the def index of the value. The
- /// following rules apply:
- ///
- /// If the isDefAccurate() method returns false then def does not contain the
- /// index of the defining MachineInstr, or even (necessarily) to a
- /// MachineInstr at all. In general such a def index is not meaningful
- /// and should not be used. The exception is that, for values originally
- /// defined by PHI instructions, after PHI elimination def will contain the
- /// index of the MBB in which the PHI originally existed. This can be used
- /// to insert code (spills or copies) which deals with the value, which will
- /// be live in to the block.
class VNInfo {
private:
enum {
HAS_PHI_KILL = 1,
REDEF_BY_EC = 1 << 1,
IS_PHI_DEF = 1 << 2,
- IS_UNUSED = 1 << 3,
- IS_DEF_ACCURATE = 1 << 4
+ IS_UNUSED = 1 << 3
};
+ MachineInstr *copy;
unsigned char flags;
- union {
- MachineInstr *copy;
- unsigned reg;
- } cr;
public:
typedef BumpPtrAllocator Allocator;
@@ -76,20 +61,19 @@ namespace llvm {
SlotIndex def;
/// VNInfo constructor.
- /// d is presumed to point to the actual defining instr. If it doesn't
- /// setIsDefAccurate(false) should be called after construction.
VNInfo(unsigned i, SlotIndex d, MachineInstr *c)
- : flags(IS_DEF_ACCURATE), id(i), def(d) { cr.copy = c; }
+ : copy(c), flags(0), id(i), def(d)
+ { }
/// VNInfo construtor, copies values from orig, except for the value number.
VNInfo(unsigned i, const VNInfo &orig)
- : flags(orig.flags), cr(orig.cr), id(i), def(orig.def)
+ : copy(orig.copy), flags(orig.flags), id(i), def(orig.def)
{ }
/// Copy from the parameter into this VNInfo.
void copyFrom(VNInfo &src) {
flags = src.flags;
- cr = src.cr;
+ copy = src.copy;
def = src.def;
}
@@ -97,23 +81,23 @@ namespace llvm {
unsigned getFlags() const { return flags; }
void setFlags(unsigned flags) { this->flags = flags; }
+ /// Merge flags from another VNInfo
+ void mergeFlags(const VNInfo *VNI) {
+ flags = (flags | VNI->flags) & ~IS_UNUSED;
+ }
+
/// For a register interval, if this VN was definied by a copy instr
/// getCopy() returns a pointer to it, otherwise returns 0.
/// For a stack interval the behaviour of this method is undefined.
- MachineInstr* getCopy() const { return cr.copy; }
+ MachineInstr* getCopy() const { return copy; }
/// For a register interval, set the copy member.
/// This method should not be called on stack intervals as it may lead to
/// undefined behavior.
- void setCopy(MachineInstr *c) { cr.copy = c; }
+ void setCopy(MachineInstr *c) { copy = c; }
- /// For a stack interval, returns the reg which this stack interval was
- /// defined from.
- /// For a register interval the behaviour of this method is undefined.
- unsigned getReg() const { return cr.reg; }
- /// For a stack interval, set the defining register.
- /// This method should not be called on register intervals as it may lead
- /// to undefined behaviour.
- void setReg(unsigned reg) { cr.reg = reg; }
+ /// isDefByCopy - Return true when this value was defined by a copy-like
+ /// instruction as determined by MachineInstr::isCopyLike.
+ bool isDefByCopy() const { return copy != 0; }
/// Returns true if one or more kills are PHI nodes.
bool hasPHIKill() const { return flags & HAS_PHI_KILL; }
@@ -156,16 +140,6 @@ namespace llvm {
else
flags &= ~IS_UNUSED;
}
-
- /// Returns true if the def is accurate.
- bool isDefAccurate() const { return flags & IS_DEF_ACCURATE; }
- /// Set the "is def accurate" flag on this value.
- void setIsDefAccurate(bool defAccurate) {
- if (defAccurate)
- flags |= IS_DEF_ACCURATE;
- else
- flags &= ~IS_DEF_ACCURATE;
- }
};
/// LiveRange structure - This represents a simple register range in the
@@ -231,8 +205,7 @@ namespace llvm {
typedef SmallVector<LiveRange,4> Ranges;
typedef SmallVector<VNInfo*,4> VNInfoList;
- unsigned reg; // the register or stack slot of this interval
- // if the top bits is set, it represents a stack slot.
+ const unsigned reg; // the register or stack slot of this interval.
float weight; // weight of this interval
Ranges ranges; // the ranges in which this register is live
VNInfoList valnos; // value#'s
@@ -248,11 +221,8 @@ namespace llvm {
};
- LiveInterval(unsigned Reg, float Weight, bool IsSS = false)
- : reg(Reg), weight(Weight) {
- if (IsSS)
- reg = reg | (1U << (sizeof(unsigned)*CHAR_BIT-1));
- }
+ LiveInterval(unsigned Reg, float Weight)
+ : reg(Reg), weight(Weight) {}
typedef Ranges::iterator iterator;
iterator begin() { return ranges.begin(); }
@@ -276,28 +246,29 @@ namespace llvm {
/// position is in a hole, this method returns an iterator pointing to the
/// LiveRange immediately after the hole.
iterator advanceTo(iterator I, SlotIndex Pos) {
+ assert(I != end());
if (Pos >= endIndex())
return end();
while (I->end <= Pos) ++I;
return I;
}
- void clear() {
- valnos.clear();
- ranges.clear();
- }
-
- /// isStackSlot - Return true if this is a stack slot interval.
+ /// find - Return an iterator pointing to the first range that ends after
+ /// Pos, or end(). This is the same as advanceTo(begin(), Pos), but faster
+ /// when searching large intervals.
///
- bool isStackSlot() const {
- return reg & (1U << (sizeof(unsigned)*CHAR_BIT-1));
+ /// If Pos is contained in a LiveRange, that range is returned.
+ /// If Pos is in a hole, the following LiveRange is returned.
+ /// If Pos is beyond endIndex, end() is returned.
+ iterator find(SlotIndex Pos);
+
+ const_iterator find(SlotIndex Pos) const {
+ return const_cast<LiveInterval*>(this)->find(Pos);
}
- /// getStackSlotIndex - Return stack slot index if this is a stack slot
- /// interval.
- int getStackSlotIndex() const {
- assert(isStackSlot() && "Interval is not a stack slot interval!");
- return reg & ~(1U << (sizeof(unsigned)*CHAR_BIT-1));
+ void clear() {
+ valnos.clear();
+ ranges.clear();
}
bool hasAtLeastOneValue() const { return !valnos.empty(); }
@@ -318,10 +289,9 @@ namespace llvm {
/// getNextValue - Create a new value number and return it. MIIdx specifies
/// the instruction that defines the value number.
VNInfo *getNextValue(SlotIndex def, MachineInstr *CopyMI,
- bool isDefAccurate, VNInfo::Allocator &VNInfoAllocator) {
+ VNInfo::Allocator &VNInfoAllocator) {
VNInfo *VNI =
new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), def, CopyMI);
- VNI->setIsDefAccurate(isDefAccurate);
valnos.push_back(VNI);
return VNI;
}
@@ -358,21 +328,6 @@ namespace llvm {
/// cause merging of V1/V2 values numbers and compaction of the value space.
VNInfo* MergeValueNumberInto(VNInfo *V1, VNInfo *V2);
- /// MergeInClobberRanges - For any live ranges that are not defined in the
- /// current interval, but are defined in the Clobbers interval, mark them
- /// used with an unknown definition value. Caller must pass in reference to
- /// VNInfoAllocator since it will create a new val#.
- void MergeInClobberRanges(LiveIntervals &li_,
- const LiveInterval &Clobbers,
- VNInfo::Allocator &VNInfoAllocator);
-
- /// MergeInClobberRange - Same as MergeInClobberRanges except it merge in a
- /// single LiveRange only.
- void MergeInClobberRange(LiveIntervals &li_,
- SlotIndex Start,
- SlotIndex End,
- VNInfo::Allocator &VNInfoAllocator);
-
/// MergeValueInAsValue - Merge all of the live ranges of a specific val#
/// in RHS into this live interval as the specified value number.
/// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
@@ -412,17 +367,18 @@ namespace llvm {
return index >= endIndex();
}
- bool liveAt(SlotIndex index) const;
-
- // liveBeforeAndAt - Check if the interval is live at the index and the
- // index just before it. If index is liveAt, check if it starts a new live
- // range.If it does, then check if the previous live range ends at index-1.
- bool liveBeforeAndAt(SlotIndex index) const;
+ bool liveAt(SlotIndex index) const {
+ const_iterator r = find(index);
+ return r != end() && r->start <= index;
+ }
/// killedAt - Return true if a live range ends at index. Note that the kill
/// point is not contained in the half-open live range. It is usually the
/// getDefIndex() slot following its last use.
- bool killedAt(SlotIndex index) const;
+ bool killedAt(SlotIndex index) const {
+ const_iterator r = find(index.getUseIndex());
+ return r != end() && r->end == index;
+ }
/// killedInRange - Return true if the interval has kills in [Start,End).
/// Note that the kill point is considered the end of a live range, so it is
@@ -452,20 +408,20 @@ namespace llvm {
/// FindLiveRangeContaining - Return an iterator to the live range that
/// contains the specified index, or end() if there is none.
- const_iterator FindLiveRangeContaining(SlotIndex Idx) const;
+ iterator FindLiveRangeContaining(SlotIndex Idx) {
+ iterator I = find(Idx);
+ return I != end() && I->start <= Idx ? I : end();
+ }
- /// FindLiveRangeContaining - Return an iterator to the live range that
- /// contains the specified index, or end() if there is none.
- iterator FindLiveRangeContaining(SlotIndex Idx);
+ const_iterator FindLiveRangeContaining(SlotIndex Idx) const {
+ const_iterator I = find(Idx);
+ return I != end() && I->start <= Idx ? I : end();
+ }
/// findDefinedVNInfo - Find the by the specified
/// index (register interval) or defined
VNInfo *findDefinedVNInfoForRegInt(SlotIndex Idx) const;
- /// findDefinedVNInfo - Find the VNInfo that's defined by the specified
- /// register (stack inteval only).
- VNInfo *findDefinedVNInfoForStackInt(unsigned Reg) const;
-
/// overlaps - Return true if the intersection of the two live intervals is
/// not empty.
@@ -502,7 +458,10 @@ namespace llvm {
/// isInOneLiveRange - Return true if the range specified is entirely in the
/// a single LiveRange of the live interval.
- bool isInOneLiveRange(SlotIndex Start, SlotIndex End);
+ bool isInOneLiveRange(SlotIndex Start, SlotIndex End) const {
+ const_iterator r = find(Start);
+ return r != end() && r->containsRange(Start, End);
+ }
/// removeRange - Remove the specified range from this interval. Note that
/// the range must be a single LiveRange in its entirety.
@@ -569,6 +528,46 @@ namespace llvm {
LI.print(OS);
return OS;
}
-}
+ /// ConnectedVNInfoEqClasses - Helper class that can divide VNInfos in a
+ /// LiveInterval into equivalence clases of connected components. A
+ /// LiveInterval that has multiple connected components can be broken into
+ /// multiple LiveIntervals.
+ ///
+ /// Given a LiveInterval that may have multiple connected components, run:
+ ///
+ /// unsigned numComps = ConEQ.Classify(LI);
+ /// if (numComps > 1) {
+ /// // allocate numComps-1 new LiveIntervals into LIS[1..]
+ /// ConEQ.Distribute(LIS);
+ /// }
+
+ class ConnectedVNInfoEqClasses {
+ LiveIntervals &lis_;
+ IntEqClasses eqClass_;
+
+ // Note that values a and b are connected.
+ void Connect(unsigned a, unsigned b);
+
+ unsigned Renumber();
+
+ public:
+ explicit ConnectedVNInfoEqClasses(LiveIntervals &lis) : lis_(lis) {}
+
+ /// Classify - Classify the values in LI into connected components.
+ /// Return the number of connected components.
+ unsigned Classify(const LiveInterval *LI);
+
+ /// getEqClass - Classify creates equivalence classes numbered 0..N. Return
+ /// the equivalence class assigned the VNI.
+ unsigned getEqClass(const VNInfo *VNI) const { return eqClass_[VNI->id]; }
+
+ /// Distribute - Distribute values in LIV[0] into a separate LiveInterval
+ /// for each connected component. LIV must have a LiveInterval for each
+ /// connected component. The LiveIntervals in Liv[1..] must be empty.
+ void Distribute(LiveInterval *LIV[]);
+
+ };
+
+}
#endif
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